This study was done to clarify the relationships among plants in herbaceous plant communities under different types of plantations growing in the environmental conditions of reclaimed coal gob piles. Data from 60 quadrat samples of herbaceous plant communities under different plantations on two reclaimed coal gob piles (revegetated in 2013 and 2003, respectively) at the No.5 mine in the Yangquan mining area of China were analyzed using two-way indicator species analysis (TWINSPAN), detrended correspondence analysis (DCA), and species diversity indices. Results showed that the herbaceous plant communities under different plantations were classified into 12 types (associations) by TWINSPAN, among which communities Ⅰ-Ⅴ were located on the coal gob piles revegetated in 2013 and communities Ⅵ-Ⅻ were located on those revegetated in 2003. The results of the DCA ordination of the 60 quadrats clearly reflected the relationship between the distribution of the herbaceous plant communities under different plantations and environmental gradients. The first DCA axis represented the gradient in time since restoration, in that the revegetated ages of herbaceous plant communities under different plantations gradually decreased from left to right along the first DCA axis. The second DCA axis represented the gradient in slope, such that the terrain of the reclaimed coal gob piles changed from the platform to the slope of the coal gob pile along the second DCA axis. Analysis of the species diversity of the herbaceous plant communities under different plantations showed that those on the platforms of the reclaimed coal gob piles were more diverse than those on the slopes (i.e. community Ⅴ > community Ⅱ, community Ⅻ > community Ⅶ), while those under arbor plantations were more diverse than those under shrub and herb plantations (i.e. community Ⅻ > community Ⅵ), and the community (Ⅻ) revegetated in 2003 was more diverse than that (Ⅴ) revegetated in 2013. These results indicated that the plantation type, revegetated age, and terrain type of the coal gob piles had significant effects on the species diversity of the herbaceous plant communities under different plantations on the reclaimed coal gob piles.